This invention relates to vacuum cleaners and, more particularly, to vacuum cleaners having a dirt cup filter which need not be removed for periodic cleaning.
Typical arrangements for "clean-air" vacuum systems with a reusable dirt cup involve placing a filter between the fan eye and a dirt collection cup. In some applications, the filter is removably attached to the wall surrounding the fan eye. In this arrangement, when the dirt cup is removed there is no obstruction to directly emptying the dirt from the dirt cup container. However, dust which clings to the filter is exposed and can drop off the filter unimpeded unless the dirt cup is removed over a waste receptacle.
In other reusable dirt cup arrangements, such as the arrangement described in U.S. Pat. No. 4,665,582 the filter is removably mounted inside the dirt cup so that removal of the dirt cup and the filter mounted therein effectively traps dirt in the cup until the filter is removed. However, it should be appreciated that the cloth filter must be removed from the dirt cup in order to empty the contents thereof.